Tape reel and tape cartridge having the same

ABSTRACT

There is provided a tape reel in which any of an upper flange and a lower flange is formed on both ends of a cylindrical hub having a magnetic tape wound therearound. A ring-shaped groove is formed on at least one of upper and lower ends of the outer circumference surface of the hub. Thereby, it is possible to prevent a tape edge of the magnetic tape from shifting onto any of the flanges and contain the tape edge of the magnetic tape in the groove when the magnetic tape is shifted onto the flanges.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the foreign priority benefit under Title 35, United States Code, §119 (a)-(d), of Japanese Patent Application No. 2006-126056 filed on Apr. 28, 2006 in the Japan Patent Office, the disclosure of which is herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a tape reel and a tape cartridge having the same, and more particularly to a tape reel having a tape such as a magnetic tape wound thereon and a tape cartridge having the same.

2. Description of the Related Art

As an external recording medium for a computer and the like, there has been known, for example, a magnetic tape cartridge, in which a cartridge case contains a tape reel having a magnetic tape wound thereon. Generally, the tap reel includes a hub, which is the center axle of the tape reel and has a magnetic tape wound around the outer circumference of the hub, and a pair of flanges, which radially project from the both axial ends of the hub toward the outside. For instance, the Japanese Laid-open Patent Application No. 2006-65988 discloses this kind of tape reel.

Magnetic tapes have been manufactured by reducing the thickness of the tapes and increasing the length of the tapes to be wound on tape reels so as to have a high storage capacity. Furthermore, when one of flanges and a hub are integrally formed, the tape reel, which is formed by resin molding, is provided with a rounded portion (R-shaped portion) at the corner where the flange and the hub are in contact with each other, so that it is possible to easily remove the tape reel from a molding die and prevent an excessive stress from being applied to the corner due to stress concentration. For this reason, the hub and the flange are not perpendicular to each other at the corner.

With reference to FIGS. 11A and 11B, a description will be given on a disadvantage in the case that a hub and a flange are not perpendicular to each other at the corner where the hub and the flange are in contact with each other. FIGS. 11A and 11B are cross-sectional views of a conventional tape reel in order to show a shape of a contact point of the hub and the flange and a disadvantage caused due to the shape of the contact point. FIG. 11A illustrates the situation where the tape is shifted onto the flange, and FIG. 11B illustrates the situation where the tape is further wound on the tape, which is shifted onto the flange and is folded over.

As shown in FIG. 11A, a conventional tape reel 101 includes a hub 102 and a pair of flanges 103, 104 provided on both ends of the hub 102. The hub 102 and the flange 103 are integrally formed, and as described above the tape reel 101 is provided with a rounded portion 102 a at a contact point of the hub 102 and the flange 103. In a manufacturing process for a magnetic tape cartridge, a longitudinal end of a magnetic tape MT is attached on the outer circumference surface of the hub 102 with liquid such as ethanol, water, or the like. After the magnetic tape MT is wound around the hub 102 several times, the magnetic tape MT of a predetermined length is wound on the tape reel 101. At the beginning of winding the magnetic tape MT around the outer circumference surface of the hub 102, however, an width-direction edge (tape edge) MTa of the magnetic tape MT is easily shifted onto the flange 103 along the rounded portion 102 a, which is provided at the contact point of the hub 102 and the flange 103. The methods of attaching the magnetic tape on the hub are disclosed, for example, in Japanese Laid-open Patent Application Nos. 2005-259273 and 2005-322353.

As shown in FIG. 11B, the edge MTa of the magnetic tape MT shifted onto the flange 103 is folded over due to pressure caused by the magnetic tape MT further wound thereon, thereby causing radial stripes on the further wound magnetic tape MT. The stripes then cause creases on the magnetic tape MT, and the creases decrease the adhesiveness between the magnetic tape MT and a read/write head, thereby causing an adverse effect on the quality of the recording and reproducing. The magnetic tape MT is easily shifted onto the flange 103, especially when the thickness of the tape MT is equal to or less than 8.9 μm. This has been a problem in the manufacturing of a magnetic tape cartridge having a high capacity.

SUMMARY OF THE INVENTION

The present invention has been accomplished in view of the above problem and has an object to provide a tape reel and a tape cartridge having the tape reel, by which it is possible to prevent a tape edge of a tape from being shifted onto a flange at the beginning of winding the tape and to prevent radial stripes from occurring on the tape wound on the tape reel.

According to one aspect of the present invention, there is provided a tape reel comprising a cylindrical hub having a tape wound therearound and a first flange and a second flange respectively provided on both ends of the hub. In the tape reel, the hub includes a ring-shaped groove on at least one of both end portions of an outer circumference surface of the hub.

When a tape, such as a magnetic tape, is wound around the outer circumference surface of the hub of the tape reel, the magnetic tape can slide from the center of the hub and be shifted to the first or second flange because of a slip between the hub and the magnetic tape or misalignment of the position of the magnetic tape on the hub at the beginning of the winding. In such a case, the width-direction edge of the magnetic tape crosses over the ring-shaped groove along the outer circumference surface of the hub and contacts the flange at a substantially right angle. Then, a normal force is exerted on the magnetic tape from the flange in the width direction of the magnetic tape, thereby making it difficult to have the magnetic tape further shifted to the flange.

When the magnetic tape is further shifted to the flange against the normal force applied from the flange, the width-direction edge of the magnetic tape, which is shifted onto the flange, is bent into the groove. Therefore, the magnetic tape further wound on the magnetic tape shifted onto the flange can be placed substantially parallel to the outer circumference surface of the hub without having any influence from the bent edge of the first wound magnetic tape.

According to another aspect of the present invention, there is provided the tape cartridge comprising the tape reel, a tape wound around the outer circumference surface of the hub of the tape reel, and a cartridge case rotatably containing the tape reel.

The tape cartridge contains the tape reel having the tape wound around the hub, which includes the ring-shaped groove formed on both ends of the hub, thereby making it possible to provide the tape cartridge capable of preventing the stripes on the tape wound on the tape reel.

The tape cartridge may have a configuration wherein the tape is provided with a curvature in a longitudinal direction of the tape, and the hub includes the groove on one of the both end portions of the outer circumference surface of the hub at an inner side of the curvature.

By this configuration, it is unnecessary to form the grooves on one of the both end portions of the hub, thereby simplifying the manufacturing process.

According to a still further aspect of the present invention, there is provided a method of manufacturing a tape reel including a cylindrical hub having a tape wound therearound and first and second flanges respectively provided on both ends of the hub. The method comprises the steps of integrally forming the hub and the first flange by injection molding, forming the second flange by injection molding, forming a first ring-shaped groove on a contact point of the hub and the first flange, and assembling the hub, the first flange, and the second flange.

Thereby, it is possible to prevent the tape from being shifted onto the flange at the beginning of winding the tape on the tape reel. Even when the tape is shifted onto the flange, the edge of the magnetic tape is bent into the groove and the magnetic tape further wound on the magnetic tape shifted onto the flange can be placed on the hub without any influence from the bent edge of the magnetic tape, thereby preventing the stripes on the tape wound on the tape reel.

According to a still further aspect of the present invention, there is provided a method of manufacturing a tape reel including a cylindrical hub having a tape wound therearound and first and second flanges respectively provided on both ends of the hub. The method comprises the steps of forming the hub having a ring-shaped groove on at least one of both end portions of an outer circumference surface of the hub by injection molding, forming a first flange by injection molding, forming a second flange by injection molding, and assembling the hub, the first flange, and the second flange.

Thereby, it is possible to prevent the tape from being shifted onto the flange at the beginning of winding the tape on the tape reel. Even when the tape is shifted onto the flange, the edge of the magnetic tape is bent into the groove and the magnetic tape further wound on the magnetic tape shifted onto the flange can be placed on the hub without any influence from the bent edge of the magnetic tape, thereby preventing the stripes on the tape wound on the tape reel. It is also possible to simplify the manufacturing process.

The tape reel may have a configuration wherein the groove has a width equal to or less than 1 mm and a depth equal to or less than 1 mm.

Thereby, when the magnetic tape is further shifted to the flange against the normal force applied from the flange, the width-direction edge of the magnetic tape, which is shifted onto the flange, is bent into the groove. Therefore, the magnetic tape further wound on the magnetic tape shifted onto the flange can be placed substantially parallel to the outer circumference surface of the hub without having any influence from the bent edge of the first wound magnetic tape.

The tape reel may have a configuration wherein the tape has a thickness equal to or less than 8.9 μm.

By this configuration, it is possible to prevent the tape from being shifted onto the flange, especially when the tape having the thickness equal to or less than 8.9 μm is used.

According to the present invention, it is possible to prevent the tape from being shifted onto the flange at the beginning of winding the tape on the tape reel. Furthermore, even when the tape is shifted onto the flange, the edge of the magnetic tape is bent into the groove and the magnetic tape further wound on the magnetic tape shifted onto the flange can be placed on the hub without any influence from the bent edge of the magnetic tape, thereby preventing the stripes on the tape wound on the tape reel. It is, therefore, possible to improve the production yield of the tape cartridge containing the tape reel according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The object and features of the present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIGS. 1A and 1B are exploded views of a configuration of a tape reel according to the first embodiment of the present invention, FIG. 1A is a perspective view of the tape reel, and FIG. 1B is a cross-sectional view of the tape reel taken along the surface including the rotational axis of the tape reel;

FIGS. 2A to 2C are cross-sectional views of the configuration of the tape reel according to the first embodiment, FIG. 2A illustrates a magnetic tape at the beginning of the winding, FIG. 2B illustrates that an edge of the magnetic tape is shifted onto a flange, and FIG. 2C illustrates that the magnetic tape is further wound on the magnetic tape shifted onto the flange as shown in FIG. 2B;

FIGS. 3A and 3B are views for explaining a manufacturing process of the tape reel of the first embodiment, FIG. 3A illustrates a reel member formed by injection molding, and FIG. 3B illustrates the reel member provided with a groove by an additional process;

FIGS. 4A and 4B are exploded views of a configuration of a tape reel according to the second embodiment, FIG. 4A is a perspective view of the tape reel, and FIG. 4B is a cross-sectional view of the tape reel taken along the surface including the rotational axis of the tape reel;

FIG. 5 is an exploded perspective view of a configuration of a magnetic tape cartridge according to the third embodiment;

FIG. 6 is a cross-sectional view illustrating that a magnetic tape cartridge is not chucked on a spindle provided in a magnetic tape drive apparatus;

FIG. 7 is a cross-sectional view illustrating that a magnetic tape cartridge is chucked on a spindle and is in an operational state;

FIG. 8 is a schematic view of a tape winder (magnetic tape cartridge manufacturing apparatus);

FIG. 9 is a perspective view of a tape carrier of a tape attaching device, which constitutes a tape winder;

FIGS. 10A to 10E illustrate an operation of a tape attaching device; and

FIGS. 11A and 11B are cross-sectional views of a conventional tape reel, FIG. 11A illustrates the situation where a tape is shifted onto a flange, and FIG. 11B illustrates the situation where the tape is further wound on the tape, which is shifted onto the flange and is folded over.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

With reference to FIGS. 1A and 1B, a description will be given on a configuration of a tape reel according to the first embodiment of the present invention. FIGS. 1A and 1B are exploded views of a configuration of a tape reel according to the first embodiment. FIG. 1A is a perspective view of the tape reel, and FIG. 1B is a cross-sectional view of the tape reel taken along the surface including the rotational axis of the tape reel.

A tape reel 1 of the first embodiment includes a reel member 5 and a disc-shaped upper flange 4. The reel member 5 includes a cylindrical hub 2 having the bottom and a disc-shaped lower flange 3, and the hub 2 and the lower flange 3 are integrally formed. The upper flange 4 has the same diameter as that of the lower flange 3. Ring-shaped grooves 2 a 1, 2 a 2 are formed on both ends of the outer circumference surface of the hub 2. The upper flange 4 has an opening portion in the center thereof, and a cylindrical portion 4 a projects toward the hub 2 around the opening portion. The outer diameter of the cylindrical portion 4 a is approximately equal to the inner diameter of the upper end of the hub 2, but the outer diameter of the cylindrical portion 4 a is slightly smaller than the inner diameter of the upper end of the hub 2. The cylindrical portion 4 a is fitted into an opening portion of the upper end of the hub 2 and is connected thereto so as to form the tape reel 1.

The grooves 2 a 1, 2 a 2 formed on the hub 2 have the width equal to or less than 1 mm and the depth equal to or less than 1 mm. In the case that the hub 2 has the width (space between the lower flange 3 and the upper flange 4) of 12.75 mm and a magnetic tape MT to be wound on the tape reel 1 has the width of ½ inch (12.65 mm) and the thickness of 6.6 μm, the widths of the grooves 2 a 1, 2 a 2 may range approximately from 0.05 mm to 1 mm and the depths of the grooves 2 a 1, 2 a 2 may range approximately from 0.05 mm to 1 mm.

With reference to FIGS. 2A to 2C, a description will be given on an effect of the ring-shaped grooves 2 a 1, 2 a 2 formed on both ends of the hub 2 of the tape reel 1 according to the first embodiment. FIGS. 2A to 2C are cross-sectional views of the configuration of the tape reel according to the first embodiment. FIG. 2A illustrates a magnetic tape at the beginning of the winding. FIG. 2B illustrates that an edge of the magnetic tape is shifted onto a flange. FIG. 2C illustrates that the magnetic tape is further wound on the magnetic tape shifted onto the flange as shown in FIG. 2B.

According to the first embodiment of the present invention, the hub 2 of the tape reel 1 includes the grooves 2 a 1, 2 a 2 formed on both ends of the outer circumference surface of the hub 2, specifically, on the contact points of the hub 2 and the lower flange 3 and of the hub 2 and the upper flange 4, respectively. As shown in FIG. 2A, when the magnetic tape MT is wound around the outer circumference surface of the hub 2 of the tape reel 1, the magnetic tape MT slides from the center of the hub 2 and is shifted to the lower flange 3, because of a slip between the hub 2 and the magnetic tape MT or misalignment of the position of the magnetic tape MT on the hub 2 at the beginning of the winding. In such a case, the width-direction edge MTa of the magnetic tape MT crosses over the groove 2 a 2 along the outer circumference surface of the hub 2 and contacts the lower flange 3 at a substantially right angle. Then, a normal force is exerted on the magnetic tape MT from the flange 3 in the width direction of the magnetic tape MT, thereby making it difficult to have the magnetic tape MT further shifted to the lower flange 3. For this reason, it is possible to prevent the magnetic tape MT from being shifted onto the lower flange 3.

The above description has been given to explain the case where the magnetic tape MT is shifted to the lower flange 3, but the same explanation can be applied to the case where the magnetic tape MT is shifted to the upper flange 4. The provision of the grooves 2 a 1, 2 a 2 on the both ends of the hub 2 can prevent the magnetic tape MT from being shifted onto the lower flange 3 and the upper flange 4. Therefore, the magnetic tape MT further wound on the magnetic tape MT shifted onto the flange can be placed substantially parallel to the outer circumference surface of the hub 2 without any influence from the edge of the magnetic tape MT shifted on any one of the flanges 3, 4, thereby preventing the radial stripes on the magnetic tape MT wound on the tape reel 1.

As shown in FIG. 2B, when the magnetic tape MT is further shifted to the lower flange 3 against the normal force applied from the lower flange 3, the width-direction edge MTa of the magnetic tape MT, which is shifted onto the lower flange 3, is bent into the groove 2 a 1. As shown in FIG. 2C, the edge MTa of the first wound magnetic tape MT, which is shifted to the lower flange 3, is bent into the groove 2 a 1 by the pressure of the second and later wound magnetic tape MT. Therefore, the surfaces of the second and later wound magnetic tape MT are parallel to the outer circumference surface of the hub 2 without having any influence from the bent edge MTa of the first wound magnetic tape MT. For this reason, it is possible to prevent the radial stripes on the magnetic tape MT wound on the tape reel 1.

The widths and depths of the grooves 2 a 1, 2 a 2 can be appropriately determined according to the stiffness and thickness of the magnetic tape MT, and an assumed (allowed) shift amount of the magnetic tape MT.

As mentioned above, the edge MTa of the magnetic tape MT, which is shifted to the lower flange 3, crosses over the groove 2 a 1 and contacts the lower flange 3. In this instance, the magnetic tape MT need to have the stiffness enough to cross over the groove 2 a 1 and contacts the lower flange 3 without being bent, so that the edge MTa of the magnetic tape MT contacts the lower flange 3 at a substantially right angle. Therefore, the width of the groove 2 a 1 may be determined according to the stiffness of the magnetic tape MT to be used.

The groove 2 a 1 need to have the depth such that the edge MTa of the magnetic tape MT, which is shifted onto the lower flange 3, can be bent into and contained in the groove 2 a 1. Therefore, the depth of the groove 2 a 1 can be appropriately determined according to the thickness of the magnetic tape MT, and the assumed (allowed) shift amount of the magnetic tape MT, that is, the amount that the magnetic tape MT is shifted to the lower flange 3. The width and depth of the groove 2 a 2 may be determined in the same manner as the groove 2 a 1.

When the thickness of the magnetic tape MT is equal to or less than 8.9 μm, the stiffness of the magnetic tape MT extremely decreases, and as shown in FIG. 11A, the magnetic tape MT is easily shifted onto the flange 103 in the conventional tape reel 101, in which the hub 102 and the flange 103 do not contact with each other at a right angle. For this reason, when the magnetic tape MT having the thickness equal to or less than 8.9 μm is used, the provision of the grooves 2 a 1, 2 a 2 formed on the both ends of the hub 2 can effectively prevent the magnetic tape MT from being shifted onto the flanges 3, 4.

With reference to FIGS. 3A and 3B, a description will be given on a method of manufacturing the tape reel 1 according to the first embodiment of the present invention. FIGS. 3A and 3B are views for explaining a manufacturing process of the tape reel of the first embodiment. FIG. 3A illustrates a reel member formed by injection molding, and FIG. 3B illustrates the reel member provided with a groove by an additional process.

The tape reel 1 of the first embodiment includes a reel member 5, in which the hub 2 and the lower flange 3 are integrally formed. As shown in FIG. 3A, the reel member 5 can be formed by injection molding, and in the reel member 5 the hub 2 having the groove 2 a 2 and the lower flange 3 are integrally formed. Then, the ring-shaped groove 2 a 1 can be formed on the edge of the hub 2, specifically, on the contact point of the hub 2 and the lower flange 3, by the additional process, such as cutting, as shown in FIG. 3B.

On the other hand, as shown in FIG. 1, the upper flange 4 has no configuration, such as the groove 2 a 1, that requires the additional process, and therefore the upper flange 4 having the cylindrical portion 4 a can be formed by injection molding.

Then, the cylindrical portion 4 a of the upper flange 4 is fitted into the opening portion provided on the upper end of the hub 2 of the reel member 5, and is connected thereto by ultrasonic welding, adhesion, or the like, so as to form the tape reel 1.

In the above-described tape reel 1 of the first embodiment, the grooves 2 a 1, 2 a 2 are formed on the both ends of the hub 2 on the assumption that the magnetic tape MT can be shifted to both of the lower flange 3 and the upper flange 4. However, it is possible to provide the effect of the present invention by forming one of the grooves 2 a 1, 2 a 2 on one end of the hub 2. For example, when a whole tape is cut into the magnetic tape MT having a product length, the magnetic tape MT is provided with a curvature (for example, the curvature of approximately 1 mm/m) in the longitudinal direction of the magnetic tape MT. Thereby, the magnetic tape MT is likely to be shifted to the inner side of the curvature when the magnetic tape MT is wound around the hub 2, and therefore one of the grooves 2 a 1, 2 a 2 may be formed on one end of the hub 2, to which end the tape MT is likely to be shifted according to the curvature of the magnetic tape MT.

The hub 2 may have the groove 2 a 2 on the upper flange 4 side end when the magnetic tape MT is provided with the curvature to be shifted to the upper flange 4, and the groove 2 a 1 need not be formed on the lower flange 3 side end of the hub 2. Therefore, the reel member 5 shown in FIG. 3A can be used in the tape reel 1 of the first embodiment, and it is unnecessary to perform the additional process to form the groove 2 a 1 on the hub 2, thereby simplifying the manufacturing process.

Second Embodiment

With reference to FIGS. 4A and 4B, a description will be given on a configuration of a tape reel according to the second embodiment of the present invention. FIGS. 4A and 4B are exploded views of the configuration of the tape reel according to the second embodiment. FIG. 4A is a perspective view of the tape reel, and FIG. 4B is a cross-sectional view of the tape reel taken along the surface including the rotational axis of the tape reel.

The tape reel 1 of the second embodiment is different from the tape reel 1 of the first embodiment in that the cylindrical hub 2 and the disc-shaped lower flange 3 are formed as one component, respectively, and therefore the tape reel 1 of the second embodiment comprises three members including the hub 2, the lower flange 3, and the upper flange 4.

The ring-shaped grooves 2 a 1, 2 a 2 are formed on both ends of the outer circumference surface of the hub 2. The disc-shaped lower flange 3 has an opening portion in the center thereof and a cylindrical portion 3 a projects toward the hub 2 around the opening portion. The outer diameter of the cylindrical portion 3 a is approximately equal to the inner diameter of the lower end of the hub 2, but the outer diameter of the cylindrical portion 3 a is slightly smaller than the inner diameter of the lower end of the hub 2. The upper flange 4 is a ring-shaped member having the same diameter as that of the lower flange 3. The upper flange 4 has the opening portion in the center thereof and the cylindrical portion 4 a projects downward around the opening portion. The outer diameter of the cylindrical portion 4 a is approximately equal to the inner diameter of the upper end of the hub 2, but the outer diameter of the cylindrical portion 4 a is slightly smaller than the inner diameter of the upper end of the hub 2.

The cylindrical portion 3 a and the cylindrical portion 4 a are fitted into the opening portions of the upper and lower ends of the hub 2, respectively, and are connected thereto so as to form the tape reel 1.

Because the tape reel 1 of the second embodiment, which is formed by connecting the above-mentioned three members, has the same configuration as the tape reel 1 of the first embodiment, a description on the configuration of the tape reel 1 of the second embodiment will be omitted.

Next, a description will be given on the method of manufacturing the tape reel 1 of the second embodiment.

The lower flange 3 and the upper flange 4 have the same configuration, and the both flanges can be formed by injection molding in the same manner as the upper flange 4 of the first embodiment.

The hub 2 of the second embodiment can be formed by injection molding without any additional process such as cutting, because the hub 2 has no portion that can not be formed by injection molding, like the groove 2 a 1 (see FIG. 1) of the reel member 5 in the first embodiment. Therefore, the hub 2, the lower flange 3, and the upper flange 4 can be formed by injection molding.

The cylindrical portion 3 a of the lower flange 3 and the cylindrical portion 4 a of the upper flange 4 are fitted into the opening portions of the lower and upper ends of the hub 2, respectively. Then, the upper side of the lower flange 3 and the lower side of the upper flange 4 are connected to the lower and upper ends of the hub 2, respectively, by ultrasonic welding, adhesion, or the like, so as to form the tape reel 1.

Third Embodiment

Next, a description will be given on a tape cartridge according to the third embodiment of the present invention. The tape cartridge of the third embodiment is explained by using as an example a single-reel type magnetic tape cartridge that conforms to the so-called LTO (Linear Tape Open) standard. The magnetic tape cartridge of the third embodiment contains the tape reel according to the embodiment of the present invention.

With reference to FIGS. 5 to 7, a description will be given on a configuration of a magnetic tape cartridge according to the third embodiment of the present invention. FIG. 5 is an exploded perspective view of the configuration of the magnetic tape cartridge according to the third embodiment. FIG. 6 is a cross-sectional view illustrating that a magnetic tape cartridge is not chucked on a spindle provided in a magnetic tape drive apparatus, and FIG. 7 is a cross-sectional view illustrating a the magnetic tape cartridge is chucked on a spindle and is in an operational state.

As shown in FIG. 5, a magnetic tape cartridge 10 of the third embodiment includes the single tape reel 1, on which the magnetic tape MT is wound, a splice tape S, a leader tape L, a leader pin 20, a lock plate 13, a compression coil spring 14, a release pad 15, a sliding door 16, a coil spring 17, a safety lug 18, an IC chip 19, or the like, which are all incorporated in a cartridge case 11 that is divided into a lower half 11 b and an upper half 11 a. One end of the leader tape L is coupled to a longitudinal end of the magnetic tape MT through the splice tape S. The leader pin 20 is attached to the other end of the leader tape L. The lock plate 13 and the compression coil spring 14 are used to lock the rotation of the tape reel 1. The release pad 15 is used to release the locking of the tape reel 1. The sliding door 16 is opened and closed in a magnetic tape pull-out port 11 c formed in the lower half 11 b and the upper half 11 a of the cartridge case 11. The coil spring 17 biases the sliding door 16 to the closed position of the pull-out port 11 c.

As shown in FIG. 6, the tape reel 1 includes the cylindrical hub 2 having the bottom, the disc-shaped upper flange 4, and the disc-shaped lower flange 3. The hub 2 has the magnetic tape MT wound around the outer circumference surface of the hub. The upper flange 4 and the lower flange 3 respectively project from the upper and lower ends of the outer circumference of the hub 2 in the radial direction.

The hub 2 and the lower flange 3 are integrally formed in the same manner as the tape reel 1 of the first embodiment. The cylindrical portion 4 a, which projects toward the hub 2 around the opening portion provided in the center of the upper flange 4, is fitted into the opening portion of the upper end of the hub 2. The ring-shaped grooves 2 a 1, 2 a 2 are formed on both ends of the outer circumference surface of the hub 2.

The lower portion in the center of the hub 2 is covered by a bottom wall 2 b, and on the outer circumference portion of the lower side of the bottom wall 2 b is formed a ring-shaped reel gear 2 c that engages with a metallic driving gear 23 of the spindle 21 provided in the magnetic tape drive apparatus. A reel plate 12, which is a ring-shaped metallic plate and is dedicated to sticking to a magnet, and the reel gear 2 c are arranged to face an opening portion 11 d provided on the bottom surface of the lower half 11 b.

Before the magnetic tape cartridge 10 is chucked on the spindle 21, a connecting projection 13 a of the lock plate 13, which is biased downward by the compression coil sprig 14, and a locking groove 2 d provided in the lower flange 3 are connected to each other so as to lock the tape reel 1 and prevent the rotation of the tape reel 1.

Next, a description will be given on an operation of the magnetic tape cartridge 10 when the tape cartridge 10 is chucked on the spindle 21 and is in an operational state.

As shown in FIG. 6, the metallic spindle 21 provided in the magnetic tape drive apparatus includes the ring-shaped driving gear 23 and a magnet (not shown), which are provided on a disc portion 25 fixed on the upper end of a rotary shaft 22.

In order to chuck the magnetic tape cartridge 10 on the spindle 21, the magnetic tape cartridge 10, which is loaded on a bucket (not shown) in the magnetic tape drive apparatus, is moved downward to the rotary shaft 22. Then, the driving gear 23 engages with the reel gear 2 c, and the magnet on the disc portion 25 sticks to the reel plate 12 so as to maintain the engagement. Thereby, the magnet tape cartridge 10 is in the operational state as shown in FIG. 7.

When the tape cartridge 10 is in the operational state as shown in FIG. 7, the driving gear 23 pushes a leg 15 a of the release pad 15, which projects through a through-hole 2 e formed in the bottom wall 2 b, in the direction of the upper half 11 a, so that the release pad 15 is pushed upward against the compression coil spring 14, thereby releasing the locking of the tape reel 1. Then, the tape reel 1 is rotated by the rotary shaft 22 through the driving gear 23 engaging with the reel gear 2 c.

With reference to FIGS. 8 to 10, a description will be given on a magnetic tape cartridge manufacturing apparatus for winding the magnetic tape MT on the tape reel 1 of the magnetic tape cartridge 10 of the third embodiment.

FIG. 8 is a schematic view of a tape winder (magnetic tape cartridge manufacturing apparatus) for winding a magnetic tape on the tape reel in the magnetic tape cartridge of the third embodiment. FIG. 9 is a perspective view of a tape carrier of a tape attaching device, which constitutes a tape winder. FIGS. 10A to 10E illustrate an operation of a tape attaching device for attaching an end portion of a magnetic tape on the hub of the tape reel in the magnetic tape cartridge according to the third embodiment. In the description on the magnetic tape cartridge manufacturing apparatus, the up-to-down and right-to-left directions are defined based on FIG. 8 where a tape attaching device 80 is mounted on a panel P, which is arranged vertically, of a tape winder W.

A description will be given on a configuration of the tape winder W.

The tape winder W shown in FIG. 8 is the apparatus for cutting the magnetic tape MT having a so-called pancake shape in a predetermined length, and winding the magnetic tape MT around the hub 2 of the tape reel 1 contained in the cartridge case 11. The tape winder W includes the tape attaching device 80 for attaching a longitudinal end portion MT1 of the magnetic tape MT on the hub 2 of the tape reel 1 in the cartridge case 11.

As shown in FIG. 8, the tape winder W mainly includes a tape supplying device 30, the tape attaching device 80, a blade device 40 that polishes the surface of the magnetic tape MT, cleaning devices 50, 50 that clean the both surfaces of the magnetic tape MT, a tension adjuster 60 that adjusts the tension of the running magnetic tape MT, a cartridge case supplying unit 70 that supplies the cartridge case 11 in stock to the tape attaching device 80, and a cartridge case discharging unit 90 that discharges the cartridge case 11 having the magnetic tape MT wound on the tape reel 1. A plurality of tape guides G is arranged in places of the panel P in order to guide the magnetic tape MT to the tape attaching device 80. The tape attaching device 80 also has a function of winding the magnetic tape MT around the hub 2. An operating panel to operate the tape winder W is denoted by SP in FIG. 8.

The tape supplying device 30 includes reels R1, R2, which have the magnetic tape MT wound therearound and have the pancake shape, and supplies the magnetic tape MT to the tape attaching device 80. In the tape supplying device 30, the reel R1 (or R2) is rotated by a reel driving unit (not shown) at a predetermined rotation speed so as to feed the magnetic tape MT to the tape attaching device 80. Because the tape supplying device 30 includes the reels R1 and R2, the reel R2 is substituted for the reel R1 when the reel R1 runs out of the magnetic tape MT, thereby continuously supplying the magnetic tape MT to the tape attaching device 80.

The tape attaching device 80 includes a case placing unit 81, on which the cartridge case 11 is placed, and a tape carrier 82 that carries the magnetic tape MT fed from the tape supplying device 30 into the cartridge case 11.

The case placing unit 81 is positioned in, for example, the approximately lower right portion of the panel P. The cartridge case 11 is placed in the case placing unit 81 such that the pull-out port 11 c faces the lower left portion of the panel P.

In the case placing unit 81, the tape reel 1 in the cartridge case 11 is rotatably supported, and the magnetic tape MT is wound around the hub 2 by the reel driving unit (not shown).

FIG. 9 is a perspective view of a tape carrier according to the third embodiment of the present invention.

As shown in FIG. 9, the tape carrier 82 is formed of a long block, which extends in the longitudinal direction. The tape carrier 82 is spaced horizontally from the pull-out port 11 c of the cartridge case 11 placed in the case placing unit 81 (see FIG. 8). The tape carrier 82 conveys the magnetic tape MT fed from the tape supplying device 30 by sticking a vicinity of the end portion MT1 of the tape MT to the tape carrier 82. The tape carrier 82 can move inside the cartridge case 11 through the pull-out port 11 c by an unshown driving unit such as an air cylinder.

On the upper side of the tape carrier 82 are formed, from the end portion of the tape carrier 82 (the cartridge case 11 side), a sponge mounting portion 83, the first adsorbing portion (holding portion) 84, and the second adsorbing portion 85. A placing portion 86, on which a sponge (elastic member) 87 is placed, is formed between the first adsorbing portion 84 and the second adsorbing portion 85.

The sponge mounting portion 83 is formed into a rectangular shape, and a sponge (first sponge) 88 is disposed on the sponge mounting portion 83. The sponge mounting portion 83 is supplied with alcohol (liquid) such as methanol, ethanol, or IPA (isopropanol), which is used to attach the magnetic tape MT on the hub 2, and therefore the sponge 88 is always soaked with an appropriate amount of the alcohol.

The first adsorbing portion 84 has a plurality of holes H1. The holes H1 are converged to one passage provided inside the tape carrier 82, and a vacuum pump and a compressor are connected to the passage through a hose, a changeover valve, or the like. When carrying the magnetic tape MT, the first adsorbing portion 84 adsorbs the magnetic tape MT in vacuum through the holes H1 connected to the vacuum pump via the passage. When the compressor is connected to the passage by switching the changeover valve, the first adsorbing portion 84 blows the magnetic tape MT through the holes H1 so as to attach the magnetic tape MT on the hub 2.

Similarly, the second adsorbing portion 85 has a plurality of holes H2. The holes H2 are converged to one passage provided inside the tape carrier 82, and a vacuum pump is connected to the passage through a hose, a solenoid valve, or the like. When carrying the magnetic tape MT, the second adsorbing portion 85 adsorbs the magnetic tape MT in vacuum through the holes H2 connected to the vacuum pump via the passage.

The placing portion 86 is formed into a groove shape and includes a placing surface 86 a and chamfered surfaces 86 b, 86 b, which lead from the placing surface 86 a to the first adsorbing portion 84 and the second adsorbing portion 85, respectively. Preferably, the width A of the placing surface 86 a is equal to or less than 11 mm, the length B is equal to or more than 19 mm, and the depth C is equal to or more than 0.5 mm. The width A is equal to or less than the width of the magnetic tape MT (½ inch, i.e., 12.65 mm), so that it is possible to prevent the placing portion 86 from interfering with the flanges 3, 4 of the tape reel 1 in the cartridge case 11 as shown in FIG. 5. The length B and the depth C are determined as above, and it is, therefore, possible to prevent the chamfered surfaces 86 b, 86 b from contacting the hub 2 when the placing surface 86 a contacts the hub 2.

A sponge 87 is fixed on the placing surface 86 a of the placing portion 86 by springs V. The sponge 87 may be fixed by various fastening devices, such as a two-side tape or adhesive agent.

The sponge 87 presses the magnetic tape MT on the hub 2 when the tape carrier 82 is moved upward to the hub 2. The magnetic tape MT is pressed on the hub 2 by the sponge 87 so that the alcohol applied on the hub 2 by the sponge 88 is applied on the magnetic tape MT and the magnetic tape MT is pressed on the hub 2 along the form of the hub 2.

The tape carrier 82 only includes the holes H1, H2, through which the magnetic tape MT is adsorbed in vacuum, and the passages connected to the holes H1, H2, so that it is possible to reduce the thickness of the tape carrier 82 and reduce the size of the tape carrier 82 according to the size of the pull-out port 11 c of the cartridge case 11.

With reference to FIGS. 8 to 10, a description will be given on an operation of the tape winder W (magnetic tape cartridge manufacturing apparatus).

In the tape winder W as shown in FIG. 8, one cartridge case 11 is supplied from the cartridge case supplying unit 70, in which the cartridge cases 11 are stored in stock, and then one of the cartridge cases 11 is placed in the case placing unit 81 in such a way that the tape reel 1 in the cartridge case 11 is rotatably supported. The magnetic tape MT is fed from the tape supplying device 30 to the tape attaching device 80 via the blade device 40, the cleaning devices 50, 50, and the tension adjuster 60.

In the tape attaching device 80, the tape carrier 82 holds the end portion MT1 of the magnetic tape MT fed from the tape supplying device 30, and attaches the end portion MT1 on the hub 2 of the tape reel 1 in the cartridge case 11, which is placed in the case placing unit 81.

With reference to FIGS. 10A to 10E, a description will be given on an operation of the tape attaching device 80. FIGS. 10A to 10E illustrate an operation of the tape attaching device 80.

As shown in FIG. 10A, the magnetic tape MT is adsorbed in vacuum through the holes H1, H2 (see FIG. 9) connected to the vacuum pump (not shown) via the passage. As shown in FIG. 10B, the tape carrier 82 is moved horizontally into the cartridge case 11 so that the sponge 88 contacts the hub 2 in the cartridge case 11. Thereby, the appropriate amount of alcohol soaked in the sponge 88 is applied on the hub 2.

As shown in FIG. 10C, the tape carrier 82 is moved forward until the placing portion 86 is positioned under the hub 2. Then, as shown in FIG. 10D, the hub 2 is rotated and the tape carrier 82 is moved upward, thereby pressing the magnetic tape MT on the hub 2 with the pressing force of, for example, 0.005 MPa. By this operation, as shown in the enlarged view on the right side of FIG. 10D, the alcohol applied on the hub 2 is applied on the magnetic tape MT and the magnetic tape MT is pressed on the hub 2 along the form of the hub 2. At the same time, the magnetic tape MT is still adsorbed in vacuum through the holes H2 while the magnetic tape MT is released from vacuum adsorption and supplied with compressed air through the holes H1, thereby blowing the end portion MT1 of the magnetic tape MT to the hub 2. Then, the end portion MT1 is attached on the hub 2.

Then, as shown in FIG. 10E, the tape carrier 82 is slightly moved downward and is pulled backward from the cartridge case 11. At the same time, the tape reel 1 is rotated at a predetermined angle and the end portion MT1 of the magnetic tape MT is wound around the hub 2. Thereby, the operation of attaching the end portion MT1 of the magnetic tape MT around the hub 2 is completed.

The grooves 2 a 1, 2 a 2 are formed on the both ends of the outer circumference surface of the hub 2 of the tape reel 1, so that it is possible to prevent the magnetic tape MT from being shifted onto the lower and upper flanges 3, 4 (see FIGS. 6 and 7) when the end portion MT1 of the magnetic tape MT is attached on the hub 2. If the magnetic tape MT is shifted to the lower and upper flanges 3, 4, the end MTa of the magnetic tape MT can be bent into the grooves 2 a 1, 2 a 2, thereby making is possible to prevent the radial stripe on the further wound magnetic tape MT.

After the end portion MT1 of the magnetic tape MT is attached on the hub 2, the tape reel 1 is rapidly rotated by the reel driving unit (not shown) provided in the case placing unit 81, and thereby a predetermined amount of the magnetic tape MT is wound on the tape reel 1. In the operation of winding the magnetic tape MT on the tape reel 1, the tape reel 1 does not rotate at a constant rotation speed. A rotation speed gradually increases from the beginning of the winding of the magnetic tape MT, and when the rotation speed reaches a predetermined speed, the tape reel 1 keeps the rotation speed for a certain period of time. Based on an expected termination time of winding the magnetic tape MT, the rotation speed gradually decreases, and the rotation stops when the winding is completed.

After the predetermined amount of the magnetic tape MT is wound on the tape reel 1, the magnetic tape MT is cut off by a cutoff device (not shown). Then, the leader tape L (see FIG. 5), which is supplied from a leader tape supplying device (not shown), is coupled to the cutoff end of the magnetic tape MT through the splice tape S by a tape coupling device (not shown), and the leader pin 20 (see FIG. 5) is attached on the other end of the leader tape L by a leader pin attaching device (not shown), thereby completing the magnetic tape cartridge 10 (see FIG. 5). When the magnetic tape cartridge 10 is completed, the case placing unit 81 releases the supported cartridge case 11 (magnetic tape cartridge 10), in which the magnetic tape MT is wound on the tape reel 1. The released cartridge case 11 is then discharged through the cartridge case discharging unit 90.

According to the above-mentioned manufacturing method, the magnetic tape cartridge 10 can be provided, by which it is possible to prevent the stripe on the magnetic tape wound on the tape reel 1 and then improve production yield.

According to the first and second embodiments of the present invention, the tape reels 1 are formed of the two members and the three members, respectively, but any one of the tape reels 1 may be configured in combination with other functional members. The manufacturing method is not limited to the above-mentioned method. The material, of which the tape reel 1 is made, is not limited to resin, and may be metal or the combination of resin and metal.

According to the third embodiment of the present invention, the magnetic tape cartridge 10 is a single reel type magnetic tape cartridge, but the present invention may be applied to a double reel type magnetic tape cartridge, in which the tape cartridge configured according to the present invention is used. The tape to be wound on the tape reel is not limited to the magnetic tape, and the present invention may be applied to tapes for other applications. 

1. A tape reel comprising: a cylindrical hub having a tape wound therearound; and a first flange and a second flange respectively provided on both ends of the hub, wherein the hub includes a ring-shaped groove on at least one of both end portions of an outer circumference surface of the hub.
 2. The tape reel according to claim 1, wherein the groove has a width equal to or less than 1 mm and a depth equal to or less than 1 mm.
 3. The tape reel according to claim 1, wherein the tape has a thickness equal to or less than 8.9 μm.
 4. The tape reel according to claim 2, wherein the tape has a thickness equal to or less than 8.9 μm.
 5. A tape cartridge comprising: the tape reel according to claim 1; a tape wound around the outer circumference surface of the hub of the tape reel; and a cartridge case rotatably containing the tape reel.
 6. The tape cartridge according to claim 5, wherein the tape is provided with a curvature in a longitudinal direction of the tape, and the hub includes the groove on one of the both end portions of the outer circumference surface of the hub at an inner side of the curvature.
 7. The tape cartridge according to claim 5, wherein the groove has a width equal to or less than 1 mm and a depth equal to or less than 1 mm.
 8. The tape cartridge according to claim 5, wherein the tape has a thickness equal to or less than 8.9 μm.
 9. A method of manufacturing a tape reel including a cylindrical hub having a tape wound therearound and first and second flanges respectively provided on both ends of the hub, the method comprising the steps of: integrally forming the hub and the first flange by injection molding; forming the second flange by injection molding; forming a first ring-shaped groove on a contact point of the hub and the first flange; and assembling the hub, the first flange, and the second flange.
 10. The method of manufacturing the tape reel according to claim 9, further comprising the step of forming a ring-shaped second groove on the end portion of the outer circumference surface of the hub on an opposite side to the first groove when the hub and the first flange are integrally formed by injection molding.
 11. A method of manufacturing a tape reel including a cylindrical hub having a tape wound therearound and first and second flanges respectively provided on both ends of the hub, the method comprising the steps of: forming the hub having a ring-shaped groove on at least one of both end portions of an outer circumference surface of the hub by injection molding; forming a first flange by injection molding; forming a second flange by injection molding; and assembling the hub, the first flange, and the second flange.
 12. The method of manufacturing the tape reel according to claim 11, further comprising the step of forming ring-shaped grooves on the both end portions of the outer circumference surface of the hub. 